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Commit Graph

32 Commits

Author SHA1 Message Date
Axel Lin
6030f42d20 i3c: master: Use dev_to_i3cmaster()
Since we have dev_to_i3cmaster() available, use it.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-08-27 09:43:59 +02:00
Wenwen Wang
7afe9a4e56 i3c: master: fix a memory leak bug
In i3c_master_getmwl_locked(), the buffer used for the dest payload data is
allocated using kzalloc() in i3c_ccc_cmd_dest_init(). Later on, the length
of the dest payload data is checked against 'sizeof(*mwl)'. If they are not
equal, -EIO is returned to indicate the error. However, the allocated
buffer is not deallocated on this path, leading to a memory leak.

To fix the above issue, free the buffer before returning the error.

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-08-12 10:11:29 +02:00
Przemyslaw Gaj
b1ac3a4b9a i3c: add addr and lvr to i2c_dev_desc structure
I need to store address and lvr value for I2C devices without static definition
in DT. This allows secondary master to transmit DEFSLVS command properly.

Main changes between v4 and v5:
- Change in defslvs to use addr and lvr from i2c_dev_desc structure
- Change in CDNS and DW drivers to use addr and lvr from i2c_dev_desc structure

Signed-off-by: Przemyslaw Gaj <pgaj@cadence.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-08-11 10:48:28 +02:00
Andy Shevchenko
fd3f8f3118 i3c: master: cdns: Use for_each_set_bit()
This simplifies and standardizes slot manipulation code
by using for_each_set_bit() library function.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-08-11 10:45:52 +02:00
Nishka Dasgupta
91227632fc i3c: master: Add of_node_put() before return
Each iteration of for_each_available_childe_of_node puts the previous
node, but in the case of a return from the middle of the loop, there
is no put, thus causing a memory leak. Add an of_node_put before the
return.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-08-11 10:45:51 +02:00
Vitor Soares
934d24a5e1 i3c: move i3c_device_match_id to device.c and export it
Some I3C device drivers need to know which entry matches the
i3c_device object passed to the probe function

Let's move i3c_device_match_id() to device.c and export it so it can be
used by drivers.

Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-07-27 11:22:19 +02:00
Linus Torvalds
96407298ff * Drop support for 10-bit I2C addresses
* Add support for limited bus mode
 * Fix the Cadence DT binding doc
 * Use struct_size() to allocate a DEFSLVS packet
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Merge tag 'i3c/for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux

Pull ic3 updates from Boris Brezillon:

 - Drop support for 10-bit I2C addresses

 - Add support for limited bus mode

 - Fix the Cadence DT binding doc

 - Use struct_size() to allocate a DEFSLVS packet

* tag 'i3c/for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux:
  i3c: master: Use struct_size() helper
  dt-bindings: i3c: cdns: Use correct cells for I2C device
  i3c: dw: add limited bus mode support
  i3c: add mixed limited bus mode
  i3c: fix i2c and i3c scl rate by bus mode
  dt-bindings: i3c: Document dropped support for I2C 10 bit devices
  i3c: Drop support for I2C 10 bit addresing
2019-07-09 09:04:31 -07:00
Gustavo A. R. Silva
ede2001569 i3c: master: Use struct_size() helper
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes, in particular in the
context in which this code is being used.

So, replace the following form:

sizeof(*defslvs) + ((ndevs - 1) * sizeof(struct i3c_ccc_dev_desc))

with:

struct_size(defslvs, slaves, ndevs - 1)

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-07-04 12:05:14 +02:00
Vitor Soares
f467907c1c i3c: dw: add limited bus mode support
This patch add limited bus mode support for DesignWare i3c master

Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: <linux-kernel@vger.kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-06-20 09:23:22 +02:00
Vitor Soares
cbf4f7325a i3c: add mixed limited bus mode
The i3c bus spec defines a bus configuration where i2c devices don't
have a 50ns filter but support SCL running at SDR max rate (12.5MHz).

This patch introduces the limited bus mode so that users can use
a higher speed in presence of i2c devices index 1.

Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: <linux-kernel@vger.kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-06-20 09:23:22 +02:00
Vitor Soares
ecc8fb54bd i3c: fix i2c and i3c scl rate by bus mode
Currently the I3C framework limits SCL frequency to FM speed when
dealing with a mixed slow bus, even if all I2C devices are FM+ capable.

The core was also not accounting for I3C speed limitations when
operating in mixed slow mode and was erroneously using FM+ speed as the
max I2C speed when operating in mixed fast mode.

Fixes: 3a379bbcea ("i3c: Add core I3C infrastructure")
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: <stable@vger.kernel.org>
Cc: <linux-kernel@vger.kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-06-20 09:23:22 +02:00
Przemyslaw Gaj
88c5032244 i3c: Drop support for I2C 10 bit addresing
This patch drops support for I2C devices with 10 bit addressing. When I2C
device with 10 bit address is defined in DT, I3C master registration fails.

Address space for I2C devices has been reduced and ->i2c_funcs() hook has been
removed.

Because this patch series dropped support for 10 bit I2C devices, support is
also dropped in Cadence I3C master driver and Synopsys DesignWare I3C master
driver.

Signed-off-by: Przemyslaw Gaj <pgaj@cadence.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-05-28 09:39:53 +02:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Linus Torvalds
80104bb06b * Fix a shift wrap bug in the core
* Remove dead code in the DW driver
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Merge tag 'i3c/for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux

Pull i3c update from Boris Brezillon:

 - Fix a shift wrap bug in the core

 - Remove dead code in the DW driver

* tag 'i3c/for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux:
  i3c: Fix a shift wrap bug in i3c_bus_set_addr_slot_status()
  i3c: master: dw: remove dead code from dw_i3c_master_*_xfers()
2019-05-07 08:50:40 -07:00
Dan Carpenter
476c7e1d34 i3c: Fix a shift wrap bug in i3c_bus_set_addr_slot_status()
The problem here is that addr can be I3C_BROADCAST_ADDR (126).  That
means we're shifting by (126 * 2) % 64 which is 60.  The
I3C_ADDR_SLOT_STATUS_MASK is an enum which is an unsigned int in GCC
so shifts greater than 31 are undefined.

Fixes: 3a379bbcea ("i3c: Add core I3C infrastructure")
Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-05-06 08:15:02 +02:00
Vitor Soares
907621e94d i3c: dw: Fix dw_i3c_master_disable controller by using correct mask
The controller was being disabled incorrectly. The correct way is to clear
the DEV_CTRL_ENABLE bit.

Fix this by clearing this bit.

Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: <stable@vger.kernel.org>
Fixes: 1dd728f5d4 ("i3c: master: Add driver for Synopsys DesignWare IP")
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-04-10 12:46:20 +02:00
Vitor Soares
9752c37cc8 i3c: Fix the verification of random PID
The validation of random PID should be done by checking the
boardinfo->pid instead of info.pid which is empty.

Doing the change the info struture declaration is no longer necessary.

Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: <stable@vger.kernel.org>
Fixes: 3a379bbcea ("i3c: Add core I3C infrastructure")
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-04-10 12:43:47 +02:00
Vitor Soares
124dbd750d i3c: master: dw: remove dead code from dw_i3c_master_*_xfers()
Detected by CoverityScan (Event result_independent_of_operands):
"(i3c_xfers + i).len > 65536" is always false regardless of the values
of its operands. This occurs as the logical operand of "if"

"(i2c_xfers + i).len > 65536" is always false regardless of the values
of its operands. This occurs as the logical operand of "if"

Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-03-30 08:41:44 +01:00
Linus Torvalds
c8d950ab24 - Add a /* fall-through */ comment in the dw-i3c-master driver
- Update the I3C entries in MAINTAINERS to add an IRC chan
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Merge tag 'i3c/for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux

Pull i3c updates from Boris Brezillon:

 - Add a /* fall-through */ comment in the dw-i3c-master driver

 - Update the I3C entries in MAINTAINERS to add an IRC chan

* tag 'i3c/for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux:
  i3c: master: dw-i3c-master: mark expected switch fall-through
  MAINTAINERS: Add an IRC channel for the I3C subsystem
2019-03-04 19:05:02 -08:00
Gustavo A. R. Silva
988bb4a193 i3c: master: dw-i3c-master: mark expected switch fall-through
In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.

This patch fixes the following warning:

drivers/i3c/master/dw-i3c-master.c: In function ‘dw_i3c_master_bus_init’:
drivers/i3c/master/dw-i3c-master.c:603:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
   if (ret)
      ^
drivers/i3c/master/dw-i3c-master.c:605:2: note: here
  case I3C_BUS_MODE_PURE:
  ^~~~

Warning level 3 was used: -Wimplicit-fallthrough=3

This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-02-28 09:47:53 +01:00
Jisheng Zhang
f36c1f9a8d i3c: master: dw: fix deadlock
In dw_i3c_master_irq_handler(), we already have gotten
&master->xferqueue.lock, if we try to get the same lock again in
dw_i3c_master_dequeue_xfer(), deadlock happens.

We fix this issue by introduing dw_i3c_master_dequeue_xfer_locked()
which does all what dw_i3c_master_dequeue_xfer() does without trying
to lock &master->xferqueue.lock.

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Acked-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
2019-01-26 11:14:25 +01:00
Jisheng Zhang
093c61b6a0 i3c: fix missing detach if failed to retrieve i3c dev
If we failed to retrieve the i3c dev, we should detach the i3c dev
I.E i3c_master_detach_i3c_dev().

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
2019-01-25 08:48:01 +01:00
Vitor Soares
f29fd331aa i3c: master: dw-i3c-master: fix i3c_attach/reattach
This patch fix i3c_attach/reattach functions.

During the i3c_attach the driver ignores the static address used for
SETDASA CCC command.

During the i3c_reattach the driver doesn't update master->addrs[data->index]
with new address if old_dyn_addr = 0.

Fixes: 1dd728f5d4 ("i3c: master: Add driver for Synopsys DesignWare IP")
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
2019-01-15 11:15:11 +01:00
Christophe JAILLET
0fac32f24c i3c: master: Fix an error checking typo in 'cdns_i3c_master_probe()'
Fix a cut'n'paste typo.
Checking 'master->sysclk' is expected here.

Fixes: 603f2bee2c ("i3c: master: Add driver for Cadence IP")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
2019-01-07 14:18:17 +01:00
Przemyslaw Gaj
25ac3da61b i3c: master: cdns: fix I2C transfers in Cadence I3C master driver
This patch fixes I2C transfers in Cadence I3C master driver.
There was no way to queue more than one I2C transfer before.

Fixes: 603f2bee2c ("i3c: master: Add driver for Cadence IP")
Signed-off-by: Przemyslaw Gaj <pgaj@cadence.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-12-12 17:08:32 +01:00
Dan Carpenter
afe120c777 ic3: off by one in mode_show()
This should be >= ARRAY_SIZE() to avoid reading one element beyond the
end of the array.

Fixes: 3a379bbcea ("i3c: Add core I3C infrastructure")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-12-05 17:22:58 +01:00
Dan Carpenter
840414ae59 i3c: fix an error code in i3c_master_add_i3c_dev_locked()
We should return "ret" as-is.  The "newdev" variable is a valid pointer.

Fixes: 3a379bbcea ("i3c: Add core I3C infrastructure")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-12-05 17:22:58 +01:00
Colin Ian King
2b2b283c05 i3c: master: dw: fix mask operation by using the correct operator
The masking operation on status is using a bitwise 'or' rather than
a bitwise 'and' operator, and hence the result is always non-zero
which is probably not what is intended. Fix this by using the correct
operator.

Detected by CoverityScan, CID#1475523 ("Wrong operator used")

Fixes: 88acc98a712a ("i3c: master: Add driver for Synopsys DesignWare IP")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-12-05 17:22:58 +01:00
Vitor Soares
1dd728f5d4 i3c: master: Add driver for Synopsys DesignWare IP
Add driver for Synopsys DesignWare I3C master IP

Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-12-05 17:22:58 +01:00
YueHaibing
ad15e8c0fa i3c: master: Remove set but not used variable 'old_i3c_scl_lim'
Fixes gcc '-Wunused-but-set-variable' warning:

drivers/i3c/master/i3c-master-cdns.c: In function 'cdns_i3c_master_do_daa':
drivers/i3c/master/i3c-master-cdns.c:1137:16: warning:
 variable 'old_i3c_scl_lim' set but not used [-Wunused-but-set-variable]

It never used since introdution in commit
  acfab7d324b2 ("i3c: master: Add driver for Cadence IP")

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-12-05 17:22:58 +01:00
Boris Brezillon
603f2bee2c i3c: master: Add driver for Cadence IP
Add a driver for Cadence I3C master IP.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-05 17:22:58 +01:00
Boris Brezillon
3a379bbcea i3c: Add core I3C infrastructure
Add core infrastructure to support I3C in Linux and document it.

This infrastructure adds basic I3C support. Advanced features will be
added afterwards.

There are a few design choices that are worth mentioning because they
impact the way I3C device drivers can interact with their devices:

- all functions used to send I3C/I2C frames must be called in
  non-atomic context. Mainly done this way to ease implementation, but
  this is not set in stone, and if anyone needs async support, new
  functions can be added later on.
- the bus element is a separate object, but it's tightly coupled with
  the master object. We thus have a 1:1 relationship between i3c_bus
  and i3c_master_controller objects, and if 2 master controllers are
  connected to the same bus and both exposed to the same Linux instance
  they will appear as two distinct busses, and devices on this bus will
  be exposed twice.
- I2C backward compatibility has been designed to be transparent to I2C
  drivers and the I2C subsystem. The I3C master just registers an I2C
  adapter which creates a new I2C bus. I'd say that, from a
  representation PoV it's not ideal because what should appear as a
  single I3C bus exposing I3C and I2C devices here appears as 2
  different buses connected to each other through the parenting (the
  I3C master is the parent of the I2C and I3C busses).
  On the other hand, I don't see a better solution if we want something
  that is not invasive.

Missing features:
- I3C HDR modes are not supported
- no support for multi-master and the associated concepts (mastership
  handover, support for secondary masters, ...)
- I2C devices can only be described using DT because this is the only
  use case I have. However, the framework can easily be extended with
  ACPI and board info support
- I3C slave framework. This has been completely omitted, but shouldn't
  have a huge impact on the I3C framework because I3C slaves don't see
  the whole bus, it's only about handling master requests and generating
  IBIs. Some of the struct, constant and enum definitions could be
  shared, but most of the I3C slave framework logic will be different

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-12 10:33:49 +01:00